"Not liking people and wanting to be left alone" is the hallmark of Schizoid Personality Disorder. What differentiates AvPD is a desire to connect with people but an inability to do so.

I tried to "become more avoidant." In the end it made me severely suicidal. I almost lost the battle. Proceed with caution.

I don't like small talk either, and generally refuse to engage in it. Unless there's weather phenomena, because that kind of fascinates me. Because I insist on having real conversations, I have a reputation (cringe) for being a good conversationalist. Next time you run into someone, try to actually talk to them. Tell them how you feel about something instead of simply acknowledging it. Might make all the difference for you.